The Best Movie of the Year: 'Toy Story 3' or 'The Social Network'?

With one day left in 2010, the web's two biggest film review aggregators, Rotten Tomatoes and Metacritic, both released their Best-Reviewed Movies of the Year lists. Not only are the respective rundowns different—the summer animated hit How to Train Your Dragon is a surprise number two on Rotten Tomatoes' list, but does not even appear on Metacritic's—but each site has named a different film the Best-Reviewed of the Year.

According to Rotten Tomatoes, critics liked Toy Story 3 the best, while Metacritic gives the distinction to The Social Network (Toy Story 3 ranks second with them). Neither site is wrong--their rankings are based on different mathematical ratings systems, which, though both accurate, yield different results. Slashfilm's Peter Sciretta breaks it down:

Rotten Tomatoes includes a larger sample of reviews, while Metacritic features a smaller more-selected grouping of film critics. Rotten Tomatoes calculates critic scores using a positive or
negative score for each review. One movie could be 100% fresh with all
the critics giving the movie a 7/10 grade. Metacritic attempts to gauge
the score of each critic's review (not just a positive or negative, but
a number 0 to 100) averaged together, giving you a better indication of
what the response is to any given film, and not just a percentage of
positive reviews.

For example, How To Train Your Dragon is ranked #2 for the year on
Rotten Tomatoes with a 98% fresh rating based on 146 reviews. But on
Metacritic, Dragon has a 74% average with 33 reviews. Honestly, I like
how Metacritic calculates the numbers, but their refusal to incorporate
a larger sample of film critics puts them behind Rotten Tomatoes in my
mind.